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I'm playing with EPROM/EEPROM's and I need various voltages. For one, EEPROM I need to be able to generate 5V, 12V and 14V at around 30 mA. Question is how I do that the easiest. I'm thinking I could use a 12V power supply for the Arduino itself. Then I can get both 5V and 12V from the Arduino board. But how do I then get 14V (within +/- 0.25V according to the datasheet)? Would it do with a step-up converter that can either be configured (potentiometers) or controlled by the Arduino to get the desired voltage?

The thing is, I have another EPROM that requires 12.75V +/- 0.25V so I guess for a general solution I would need some way the Arduino can programmatically set the generated step-up voltage. It would also be nice to not be dependent on e.g. 12V DC IN, but instead be able to step-up from anything-to-anything.

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  • \$\begingroup\$ You can use a discontinuous boost circuit with adc feedback in the loop. A single programmed word will drop the voltage slightly. But with the right cap size, it will stay in range. Then add a few more pulses and then program the next word. It's just software so you can hit a wide range of desired target programming voltages. Worked fine for me decades ago. I still have my logbook pages from back then (1990.) Cheap. Simple. \$\endgroup\$
    – periblepsis
    Commented May 10 at 8:11
  • \$\begingroup\$ You can make your own boost converter with a choke, a switch and a diode. Arduino will be needed for ADC (output voltage measurement) and clock/pulse generation (driving the switch). Or you can make a charge pump that doubles, triples, one-halves, or does something else with the input voltage, depending on your needs. Arduino is needed for clock generation only. \$\endgroup\$
    – Rohat Kılıç
    Commented May 10 at 8:19

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You could use a canned boost converter such as the AP3012 with feedback from a resistor divider and a mux. Choose the lowest output voltage (highest point on the divider) to correspond to 0x00 into the mux so the default output voltage is minimum.

Since the feedback reference voltage on most such devices is well under 5V, you can use a low-cost 5V mux such as the '4052.

A divider something like this:

schematic

simulate this circuit – Schematic created using CircuitLab

Some programmers such as the PICkit use a DIY boost converter with a BJT and coil, and handle feedback on the MCU chip, and that would be an interesting approach if you have the time (and the chops) to perfect the design.

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